Buggy code:
public DefaultCodeFormatterOptions ( Map settings ) { } private String getAlignment ( int alignment ) { } public Map getMap ( ) { } public void set ( Map settings ) { } public void setDefaultSettings ( ) { } public void setJavaConventionsSettings ( ) { this . allocation_expression_arguments_alignment = Integer . parseInt ( FORMATTER_COMPACT_SPLIT ) ; this . anonymous_type_declaration_brace_position = DefaultCodeFormatterConstants . END_OF_LINE ; this . array_initializer_brace_position = DefaultCodeFormatterConstants . END_OF_LINE ; this . array_initializer_continuation_indentation = 2 ; this . array_initializer_expressions_alignment = Integer . parseInt ( FORMATTER_COMPACT_SPLIT ) ; this . binary_expression_alignment = Integer . parseInt ( FORMATTER_COMPACT_SPLIT ) ; this . blank_lines_after_imports = 1 ; this . blank_lines_after_package = 1 ; this . blank_lines_before_field = 1 ; this . blank_lines_before_first_class_body_declaration = 0 ; this . blank_lines_before_imports = 1 ; this . blank_lines_before_member_type = 1 ; this . blank_lines_before_method = 1 ; this . blank_lines_before_new_chunk = 1 ; this . blank_lines_before_package = 0 ; this . block_brace_position = DefaultCodeFormatterConstants . END_OF_LINE ; this . compact_else_if = true ; this . compact_if_alignment = Integer . parseInt ( FORMATTER_COMPACT_SPLIT ) ; this . conditional_expression_alignment = Integer . parseInt ( FORMATTER_NEXT_PER_LINE_SPLIT ) ; this . continuation_indentation = 2 ; this . explicit_constructor_arguments_alignment = Integer . parseInt ( FORMATTER_COMPACT_SPLIT ) ; this . filling_space = '<seq2seq4repair_space>' ; this . format_guardian_clause_on_one_line = true ; this . indent_block_statements = true ; this . indent_body_declarations_compare_to_type_header = true ; this . indent_breaks_compare_to_cases = true ; this . indent_switchstatements_compare_to_cases = true ; this . indent_switchstatements_compare_to_switch = false ; this . insert_new_line_after_opening_brace_in_array_initializer = false ; this . insert_new_line_before_closing_brace_in_array_initializer = false ; this . insert_new_line_in_control_statements = false ; this . insert_new_line_in_empty_anonymous_type_declaration = true ; this . insert_new_line_in_empty_block = true ; this . insert_new_line_in_empty_method_body = true ; this . insert_new_line_in_empty_type_declaration = true ; this . insert_space_after_assignment_operators = true ; this . insert_space_after_binary_operator = true ; this . insert_space_after_block_close_brace = true ; this . insert_space_after_closing_paren_in_cast = true ; this . insert_space_after_colon_in_assert = true ; this . insert_space_after_colon_in_conditional = true ; this . insert_space_after_colon_in_labeled_statement = true ; this . insert_space_after_comma_in_allocation_expression = true ; this . insert_space_after_comma_in_array_initializer = true ; this . insert_space_after_comma_in_constructor_arguments = true ; this . insert_space_after_comma_in_constructor_throws = true ; this . insert_space_after_comma_in_explicitconstructorcall_arguments = true ; this . insert_space_after_comma_in_for_increments = true ; this . insert_space_after_comma_in_for_inits = true ; this . insert_space_after_comma_in_messagesend_arguments = true ; this . insert_space_after_comma_in_method_arguments = true ; this . insert_space_after_comma_in_method_throws = true ; this . insert_space_after_comma_in_multiple_field_declarations = true ; this . insert_space_after_comma_in_multiple_local_declarations = true ; this . insert_space_after_comma_in_superinterfaces = true ; this . insert_space_after_open_paren_in_parenthesized_expression = false ; this . insert_space_after_opening_paren_in_cast = false ; this . insert_space_after_postfix_operator = false ; this . insert_space_after_prefix_operator = false ; this . insert_space_after_question_in_conditional = true ; this . insert_space_after_semicolon_in_for = true ; this . insert_space_after_unary_operator = false ; this . insert_space_before_anonymous_type_open_brace = true ; this . insert_space_before_assignment_operators = true ; this . insert_space_before_binary_operator = true ; this . insert_space_before_block_open_brace = true ; this . insert_space_before_bracket_in_array_reference = false ; this . insert_space_before_bracket_in_array_type_reference = false ; this . insert_space_before_catch_expression = true ; this . insert_space_before_closing_brace_in_array_initializer = false ; this . insert_space_before_closing_paren = false ; this . insert_space_before_closing_paren_in_cast = false ; this . insert_space_before_closing_paren_in_parenthesized_expression = false ; this . insert_space_before_colon_in_assert = true ; this . insert_space_before_colon_in_case = false ; this . insert_space_before_colon_in_conditional = true ; this . insert_space_before_colon_in_default = false ; this . insert_space_before_colon_in_labeled_statement = false ; this . insert_space_before_comma_in_allocation_expression = false ; this . insert_space_before_comma_in_array_initializer = false ; this . insert_space_before_comma_in_constructor_arguments = false ; this . insert_space_before_comma_in_constructor_throws = false ; this . insert_space_before_comma_in_explicitconstructorcall_arguments = false ; this . insert_space_before_comma_in_for_increments = false ; this . insert_space_before_comma_in_for_inits = false ; this . insert_space_before_comma_in_messagesend_arguments = false ; this . insert_space_before_comma_in_method_arguments = false ; this . insert_space_before_comma_in_method_throws = false ; this . insert_space_before_comma_in_multiple_field_declarations = false ; this . insert_space_before_comma_in_multiple_local_declarations = false ; this . insert_space_before_comma_in_superinterfaces = false ; this . insert_space_before_first_argument = false ; this . insert_space_before_first_initializer = false ; this . insert_space_before_for_paren = true ; this . insert_space_before_if_condition = true ; this . insert_space_before_message_send = false ; this . insert_space_before_method_declaration_open_paren = false ; this . insert_space_before_method_open_brace = true ; this . insert_space_before_open_paren_in_parenthesized_expression = false ; this . insert_space_before_opening_brace_in_array_initializer = false ; this . insert_space_before_postfix_operator = false ; <START_BUG> this . insert_space_before_prefix_operator = true ; <END_BUG> this . insert_space_before_question_in_conditional = true ; this . insert_space_before_semicolon = false ; this . insert_space_before_switch_condition = true ; this . insert_space_before_switch_open_brace = true ; this . insert_space_before_synchronized_condition = true ; this . insert_space_before_type_open_brace = true ; this . insert_space_before_unary_operator = false ; this . insert_space_before_while_condition = true ; this . insert_space_between_brackets_in_array_reference = false ; this . insert_space_between_brackets_in_array_type_reference = false ; this . insert_space_between_empty_arguments = false ; this . insert_space_between_empty_array_initializer = false ; this . insert_space_in_catch_expression = false ; this . insert_space_in_for_parens = false ; this . insert_space_in_if_condition = false ; this . insert_space_in_switch_condition = false ; this . insert_space_in_synchronized_condition = false ; this . insert_space_in_while_condition = false ; this . insert_space_within_message_send = false ; this . keep_else_statement_on_same_line = false ; this . keep_simple_if_on_one_line = true ; this . keep_then_statement_on_same_line = true ; this . message_send_arguments_alignment = Integer . parseInt ( FORMATTER_COMPACT_SPLIT ) ; this . message_send_selector_alignment = Integer . parseInt ( FORMATTER_COMPACT_SPLIT ) ; this . method_declaration_arguments_alignment = Integer . parseInt ( FORMATTER_COMPACT_SPLIT ) ; this . method_declaration_brace_position = DefaultCodeFormatterConstants . END_OF_LINE ; this . method_throws_clause_alignment = Integer . parseInt ( FORMATTER_COMPACT_SPLIT ) ; this . multiple_fields_alignment = Integer . parseInt ( FORMATTER_COMPACT_SPLIT ) ; this . number_of_blank_lines_to_insert_at_beginning_of_method_body = 0 ; this . number_of_empty_lines_to_preserve = 1 ; this . page_width = 80 ; this . preserve_user_linebreaks = false ; this . put_empty_statement_on_new_line = true ; this . qualified_allocation_expression_arguments_alignment = Integer . parseInt ( FORMATTER_COMPACT_SPLIT ) ; this . switch_brace_position = DefaultCodeFormatterConstants . END_OF_LINE ; this . tab_size = 4 ; this . type_declaration_brace_position = DefaultCodeFormatterConstants . END_OF_LINE ; this . type_declaration_superclass_alignment = Integer . parseInt ( FORMATTER_COMPACT_SPLIT ) ; this . type_declaration_superinterfaces_alignment = Integer . parseInt ( FORMATTER_COMPACT_SPLIT ) ; this . type_member_alignment = Integer . parseInt ( FORMATTER_NO_ALIGNMENT ) ; this . use_tab = false ; } }

Fix:
this . insert_space_before_prefix_operator = false ;